Homeschool World Forum

I always enjoyed competing against someone, but that could be because I'm male - studies show that as a whole, boys are motivated by competition and girls are happy to study on their own. Of course, I also enjoyed multiplying 30-digit numbers by hand, so maybe I'm just odd period.

I think with tables it's important that they know why 5 X 7 is 35 not just that it is 35.

It has always puzzled me that students say they need a calculator or pencil and paper to find the answer to to 98*5 + 2*5. You are adding 5's, you have 98+2 5's. The answer should easily be seen to be 500.

Well, yes, if you have some experience looking at problems that way. Knowledge of how to do 98 x 5 and 2 x 5 in your head doesn't necessarily extend to realizing it's the same as (98 + 2) x 5.

David - knowing why basic math works is important, but multiplication is easy to demonstrate using manipulatives, and once it's been demonstrated once, that's all you need to know. You don't need to keep thinking about the "why". Memorization is arguably more important because it takes up the bulk of the time in basic math, and provides the big speed advantages in more advanced material. In Calculus, you are bombarded with formulas, most of which aren't explained until Calculus II. Physics has formulas that aren't explained until you take Calculus 1. The important thing is arriving at the correct answer with 100% accuracy and a high degree of speed - the "why" only matters if you don't remember the formula and have to derive it on your own.

Theodore, I disagree with you about whether or not a student should know what 98*5+2*5 is equal to. EVERY algebra student should know that 98x+2x =100x. All the above problem did was say what x is. Yes!, every (and I mean every) student should know the answer immediately. You have to have some standards in the classroom. I ALWAYS tell my students 'if it always works for letters it must always work for numbers, if it doesn't work for all numbers it doesn't work for all letters'.